Diagnostic value of radiomics in predicting Ki-67 and cytokeratin 19 expression in hepatocellular carcinoma: a systematic review and meta-analysis

Background

Radiomics have been increasingly used in the clinical management of hepatocellular carcinoma (HCC), such as markers prediction. Ki-67 and cytokeratin 19 (CK-19) are important prognostic markers of HCC. Radiomics has been introduced by many researchers in the prediction of these markers expression, but its diagnostic value remains controversial. Therefore, this review aims to assess the diagnostic value of radiomics in predicting Ki-67 and CK-19 expression in HCC.

Methods

Original studies were systematically searched in PubMed, EMBASE, Cochrane Library, and Web of Science from inception to May 2023. All included studies were evaluated by the radiomics quality score. The C-index was used as the effect size of the performance of radiomics in predicting Ki-67and CK-19 expression, and the positive cutoff values of Ki-67 label index (LI) were determined by subgroup analysis and meta-regression.

Results

We identified 34 eligible studies for Ki-67 (18 studies) and CK-19 (16 studies). The most common radiomics source was magnetic resonance imaging (MRI; 25/34). The pooled C-index of MRI-based models in predicting Ki-67 was 0.89 (95% CI:0.86-0.92) in the training set, and 0.87 (95% CI: 0.82-0.92) in the validation set. The pooled C-index of MRI-based models in predicting CK-19 was 0.86 (95% CI:0.81-0.90) in the training set, and 0.79 (95% CI: 0.73-0.84) in the validation set. Subgroup analysis suggested Ki-67 LI cutoff was a significant source of heterogeneity (I 2 = 0.0% P>0.05), and meta-regression showed that the C-index increased as Ki-67 LI increased.

Conclusion

Radiomics shows promising diagnostic value in predicting positive Ki-67 or CK-19 expression. But lacks standardized guidelines, which makes the model and variables selection dependent on researcher experience, leading to study heterogeneity. Therefore, standardized guidelines are warranted for future research.

Systematic Review Registration

https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42023427953.

The Impact of Prolonged and Intermittent Fasting on PGC-1α, Oct-4, and CK-19 Liver Gene Expression

BACKGROUND

Liver stemness refers to the high regenerative capacity of the organ. This intrinsic regeneration capacity allows the restoration of post-resection liver function in up to 50% of liver donors. Liver cirrhosis is one of the terminal liver diseases with a defect in the intrinsic regeneration capacity. Several attempts to restore intrinsic regeneration capacity by conducting in vivo studies on stem cells in various organs have shown the positive impact of fasting on stemness. An increased capacity for stem cell proliferation and regeneration was reported due to fasting. Prolonged fasting (PF) has been reported to maintain the long-term proliferative ability of hematopoietic stem cells. However, clinical trials on intermittent fasting (IF) have not conclusively given positive results for fasting individuals.

OBJECTIVES

This research aims to investigate the effect of fasting on liver stemness by comparing the expression of octamer-binding transcription factor 4 (Oct-4), cytokeratin 19 (CK-19), and peroxisome proliferator-activated receptor γ co-activator α (PGC-1α) in liver cells of fasted rabbits with rabbits fed ad libitum. This study compares two types of fasting, which are intermittent (16 hours) and prolonged (40 hours) fasting, for liver stemness and intrinsic regenerative capacity.

METHODS

A total of 18 rabbits were conditioned into 3 different groups. The first group was subjected to an ad libitum diet, the second to intermittent fasting (16-hour fasting), and the third to prolonged fasting (40-hour fasting). Afterward, the RNA was extracted from the liver tissues of each rabbit and analyzed via real-time quantitative reverse transcriptase polymerase chain reaction (qRT-PCR). Relative expression was calculated using the Livak method.

RESULTS

Compared to the ad libitum diet, a greater increase was reported in PGC-1α, upregulated Oct4, and steady CK-19 gene expressions in the livers of intermittent fasting rabbits. Prolonged fasting increased PGC1α, reduced liver stemness, and a statistically insignificant decrease in intrinsic liver regenerative capacity.

CONCLUSION

Intermittent fasting indicates preferable molecular alterations in liver stemness and intrinsic regenerative capacity compared to prolonged fasting.

Metastasis to the F344 Rat Pancreas from Lung Cancer Induced by 4-(Methylnitrosamino)- 1-(3-pyridyl)-1-butanone and Enantiomers of Its Metabolite 4-(Methylnitrosamino)-1-(3-pyridyl)- 1-butanol, Constituents of Tobacco Products

Lung cancer is the most common cause of cancer-related deaths in humans worldwide. There is strong evidence that the tobacco-specific nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) and its metabolite 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) play an important role in carcinogenesis caused by tobacco products. NNK and racemic NNAL are reported to induce lung and pancreatic tumors in rats. The carcinogenicity in Fischer 344 rats of NNK, NNAL, and its enantiomers ( R)-NNAL and ( S)-NNAL has been studied recently, and all test compounds induced significant numbers of lung tumors. We report here the detailed histopathological and immunohistochemical characterization of these tumors and their aggressive nature as shown by their metastasis locally and to the pancreas. The spectrum of treatment-related histopathological findings comprised pulmonary alveolar/bronchiolar (A/B) epithelial hyperplasia, A/B adenomas, and A/B carcinomas. A/B carcinomas frequently exhibited local invasion/metastasis within the mediastinum and thoracic cavity and distant metastasis to the pancreas that was confirmed by immunohistochemistry using the lung-specific markers prosurfactant protein-C and club (Clara) cell-10. Our observation regarding metastasis to the pancreas was an important, and unexpected, finding in this study both for the experimental animal model and potential human relevance.

Differential expression of PIWIL2 in papillary thyroid cancers

Thyroid cancer is the most common type of endocrine malignancy and a leading cause of death among endocrine organ-related cancers. Similar to other types of cancers, early diagnosis of thyroid cancer is important to increase the survival and treatment of this disease. Several immunohistochemical markers are used in the differential diagnosis of thyroid papillary carcinoma. Also, increasing evidence indicates that P-element induced wimpy testis like 2 (PIWIL2) is an RNA-binding protein involved in the induction and progression of numerous types of human malignancies such as lung, breast, colon, prostate and cervix cancers. However, the role of PIWIL2 was poorly investigated in thyroid cancers. Accordingly, aim of the present study was to elucidate the relationship between PIWIL2 and thyroid cancers. The expression level of PIWIL2 was determined by analyzing both protein and mRNA levels in papillary and micropapillary carcinoma tissues by using immunohistochemistry and real-time PCR methods, respectively. Immunohistochemical analysis of HBME-1, galectin-3 and CK-19 was also performed. Similar to other immune markers of HBME-1, galectin-3 and CK-19, protein expression levels of PIWIL2 was significantly up-regulated in both papillary and micropapillary thyroid cancers (p < 0.01). Moreover, consistent with protein expression levels, mRNA expression levels of PIWIL2 was elevated in both papillary and micropapillary thyroid cancer tissues. Yet, mRNA expression changes were statistically insignificant. In conclusion, results of the current study suggest that PIWIL2 can be involved in thyroid cancer tumorigenesis and can be used as a novel predictive biomarker and/or therapeutic target.

Study of Immunohistochemical Markers (CK-19, CD-56, Ki-67, p53) in Differentiating Benign and Malignant Solitary Thyroid Nodules with special Reference to Papillary Thyroid Carcinomas

INTRODUCTION

Solitary Thyroid Nodule (STN) has provoked increased concern owing to higher incidence of malignancy. The inter and intra observer variation in the histomorphological diagnosis of Papillary Thyroid Carcinomas (PTC) may sometimes pose a diagnostic difficulty.

AIM

This study was undertaken to analyse immunohistochemical (IHC) markers (CK-19, CD-56, p53, Ki-67) to differentiate between benign and malignant surgically resected STN along with their utility in the identification of PTC.

MATERIALS AND METHODS

The present cross sectional study was conducted over a period of 4 years. A technique of manual tissue array was employed for cases subjected to IHC. The primary antibodies used were CK-19, CD-56, p53 and Ki-67. Analysis of the expression of IHC markers (p53, Ki-67) to distinguish between benign and malignant STN was done. Evaluation and correlation of expression of IHC markers (CK-19, CD-56) to determine its utility in reaching definitive diagnosis and assessing prognosis of PTC was tried. Results were subjected to statistical analysis. The results were considered to be significant when the p-value <0.05.

RESULTS

Out of the 160 cases of surgically resected STN specimens, 68 cases were non-neoplastic, 24 cases were benign and 68 cases were of malignant tumours (7 cases of follicular carcinoma (FCa), 61 cases of PTC). CK-19 was found to be a sensitive (83.61%) and a highly specific positive marker (100%) for the diagnosis of PTC. The difference in CD-56 expression between PTC and non-PTC group was found to be highly statistically significant. CD-56 was found to be a sensitive (85.86%) and specific (82.25%) negative marker in differentiating PTC from follicular lesions/neoplasms. The difference in p53 expression between the malignant and non-malignant STN cases was found to be highly statistically significant with a sensitivity and specificity 85.29% and 70.65% respectively. The statistical difference in mean Ki-67 Labeling Index (LI) was found to be significant between PTC versus FA, PTC versus non-neoplastic lesions, FA versus FCa and FVPTC versus FA.

CONCLUSION

The panel of four IHC markers (CK-19, CD-56, p53, Ki-67) may be used for differentiating doubtful benign STN cases from malignant ones and also for definitive diagnosis of PTC along with histopathological examination.

The Role of CTCs as Tumor Biomarkers

Detection of Circulating Tumor Cells (CTCs) in peripheral blood can serve as a "liquid biopsy" approach and as a source of valuable tumor markers. CTCs are rare, and thus their detection, enumeration and molecular characterization are very challenging. CTCs have the unique characteristic to be non-invasively isolated from blood and used to follow patients over time, since these cells can provide significant information for better understanding tumour biology and tumour cell dissemination. CTCs molecular characterization offers the unique potential to understand better the biology of metastasis and resistance to established therapies and their analysis presents nowadays a promising field for both advanced and early stage patients. In this chapter we focus on the latest findings concerning the clinical relevance of CTC detection and enumeration, and discuss their potential as tumor biomarkers in various types of solid cancers. We also highlight the importance of performing comparison studies between these different methodologies and external quality control systems for establishing CTCs as tumor biomarkers in the routine clinical setting.

The expression of CK-19 gene in circulating tumor cells of blood samples of metastatic breast cancer women

Breast cancer is the most common cancer in women worldwide. Breast cancer in one third of all patients will go on to metastasis, which is the main cause of mortality in cancer cases. Tumor cells detach from primary tumor and enter into the circulation as circulating tumor cells (CTCs) which can form metastatic lesions. In this study, the expression of CK-19 gene in blood samples of metastatic breast cancer women was investigated and compared to control group. Twenty one patients with metastatic breast cancer and 20 healthy female volunteers enrolled in this study. For every patient and healthy donor 10 ml peripheral blood was collected. Peripheral blood mononuclear cells were isolated by gradient density centrifugation using Ficoll Hypaque. CK-19 gene expression was evaluated using SYBR green-based real-time quantitative polymerase chain reaction assays. The relative expression level of CK-19 was calculated using the 2(-ΔΔCt) analysis method. The mean of CK-19 expression was increased in metastatic breast cancer when compared to those of normal women (1.50 fold). 38.1% of the metastatic breast cancer patients showed CK-19 mRNA-detectable CTCs in their blood samples. There was no statistically significant difference between the relative expression level of CK-19 and the patient's clinicopathological characteristics. According to our knowledge, no study for determining CTC biomarkers in Iranian breast cancer women patients has yet been established. Our results suggest that the CK-19 mRNA expression investigation may be useful for monitoring CTCs in the blood of metastatic breast cancer patients, predicting early metastatic relapse or monitoring of anti-metastasis treatments.

Origin of ameloblastoma from Basal cells of the oral epithelium- establishing the relation using neuroectodermal markers

BACKGROUND AND OBJECTIVES

Basal cell layer of the oral epithelium has been rightfully regarded as a potential source of odontogenic tumours and cysts, but, without substantial evidence. Also, whether the basal cell layer retains within it, some properties of ectomesenchyme, which was imbibed during the early embryogenesis and hence its neuroectodermal relation, is not known. Here, an attempt is made to establish the hidden neuroectodermal potential of the oral epithelium, especially the basal layer, by observing the expression of known neuroectodermal markers, NSE (Neuron Specific Enolase), Synaptophysin and CD99. The expression of the same markers has also been studied in Ameloblastoma, connecting it with oral epithelium, in turn establishing basal cell layer as a potential source of Ameloblastoma.

MATERIALS AND METHODS

Sections of formalin fixed, paraffin embedded tissue samples of 20 cases of Ameloblastoma and 10 cases of Normal Retromolar mucosa, were stained immunohistochemically with NSE, Synaptophysin, CD99 and also with CK-19 and evaluated for positive expression.

RESULTS

Positive reaction was obtained in all the cases of Ameloblastoma and NRM (Normal Retromolar mucosa) with NSE, all the cases of Ameloblastoma and eight cases of NRM with Synaptophysin and in six cases of Ameloblastoma and NRM with CD99. The staining was diffuse and more marked in case of NSE than Synaptophysin and CD99. CK19 staining done to assure that the tissue antigenicity was maintained was positive in all the samples.

INTERPRETATION AND CONCLUSION

A strong relationship between the neuroectoderm, Ameloblastoma and the basal layer of the oral epithelium is established by the study. It favours the hypothesis that the basal cell layer of oral mucosa may be the sought out culprit in most cases of the Ameloblastomas, especially those occurring in the non-tooth bearing area. This would call for the need to incorporate additional therapy in the form of mucosal striping along with the conventional treatment.

Trisomy of the Dscr1 gene suppresses early progression of pancreatic intraepithelial neoplasia driven by oncogenic Kras

Individuals with Down syndrome exhibit remarkably reduced incidence of most solid tumors including pancreatic cancer. Multiple mechanisms arising from the genetic complexity underlying Down syndrome has been suggested to contribute to such a broad cancer protection. In this study, utilizing a genetically engineered mouse model of pancreatic cancer, we demonstrate that trisomy of the Down syndrome critical region-1 (Dscr1), an endogenous calcineurin inhibitor localized on chromosome 21, suppresses the progression of pancreatic intraepithelial neoplasia-1A (PanIN-1A) to PanIN-1B lesions without affecting the initiation of PanIN lesions mediated by oncogenic Kras(G12D). In addition, we show that Dscr1 trisomy attenuates nuclear localization of nuclear factor of activated T-cells (NFAT) accompanied by upregulation of the p15(Ink4b) tumor suppressor and reduction of cell proliferation in early PanIN lesions. Our data suggest that attenuation of calcineurin-NFAT signaling in neoplastic pancreatic ductal epithelium by a single extra copy of Dscr1 is sufficient to inhibit the progression of early PanIN lesions driven by oncogenic Kras, and thus may be a potential mechanism underlying reduced incidence of pancreatic cancer in Down syndrome individuals.

Tube-like structures with co-expression of D2-40 and CD34: newly formed vasculatures?

Background: A great number of in vitro and in vivo studies have suggested that many pathways or factors can stimulate angiogenesis and lymphangiogenesis, which facilitate tumor progression and metastasis. However, the morphological and immunohistochemical profile of newly formed vasculatures has not been elucidated, making it difficult to differentiate them from the pre-existing ones, and to identify their unique molecular profiles for diagnosis and therapeutic interventions.

Experimental findings: As cytokeratin (CK)-19 is a well-recognized stem cell marker and CK-19-positive cells are frequently detected in the peripheral blood of patients with metastatic cancer, our recent studies have assessed the involvement of CK-19 in the formation of new vasculatures in primary colorectal cancer (CRC) tissues. Our studies showed that a subset of lymph node-positive cases harbored some isolated normal epithelial structures with distinct CK-19 immunostaining within an otherwise CK-19-negative background. These structures are exclusively located within or adjacent to lymphoid follicles and are often surrounded by tube-like structures expressing lymphatic endothelial marker D2-40. Similar structures are more frequently seen at the junctions between pre-invasive and invasive CRC with the following features: (1). they consist of a single layer of endothelial cells that express both D2-40 and CD34, (2). their endothelial walls are often incomplete with disseminated cells protruding into the adjacent stroma, and (3). they are exclusively associated with disseminated CK-19-positive cells

Hypothesis: Based on these findings, we propose that these tube-like structures represent newly formed vasculatures, which are derived by the convergence of aberrant lymphocyte infiltration and tumor stem cells. Because of their close physical proximity, tumor stem cells within the epithelial and stromal components contribute equally and coordinately to the morphogenesis of new vasculatures, which constitutes the basis for the unique morphologic and immunohistochemical features of newly formed vasculatures. Our hypothesis appears to be applicable to all epithelium-derived cancers.